scaphoid fracture
The scaphoid is one of 8 small bones in the wrist joint, called carpal bones, which together allow the wrist to bend normally. The carpal bones form two rows across the wrist, and the scaphoid bone is an important connection between those two rows that is instrumental for full and painless motion.
Causes
Scaphoid fractures commonly occur following a fall onto the hand or wrist. A broken scaphoid bone typically produces pain along the thumb side of the wrist, which is worse when pressure is applied or when trying to bend the wrist. The pain may subside after several weeks or months in some scaphoid fractures, resulting in many patients believing they just suffered a “sprain”. Unfortunately, the pain will inevitably return as the unhealed scaphoid fracture later results in wrist arthritis.
Diagnosis
If you have pain in your wrist after a fall, x-rays are important to rule out a fracture. Delayed treatment can cause healing problems. The scaphoid bone has a very tenuous and fragile blood supply. The normal blood flow to the bone can be disrupted by a fracture that shifts the bone. Additionally, if a diagnosis is not made and the wrist is used normally, the motion across the fracture site can prevent the two pieces from healing together normally. Sometimes, x-rays do not show the fracture immediately after the injury if the fracture is not displaced. When there is pain in the area of the scaphoid, repeating an x-ray ~2 weeks later or having an MRI or CT scan can be helpful to make a diagnosis.
Non-surgical treatment
Many “non-displaced” scaphoid fracture will heal uneventfully with 6-8 weeks in a cast that immobilizes the thumb and wrist.
Surgery
Scaphoid fractures that have gapped open, shifted, or “displaced”, are oftentimes treated surgically. The two fracture pieces are lined up, and a screw is placed within the bone to both stabilize the fracture and “compress” the two pieces together. This dramatically increases the chance of healing.
Typically after surgery, a cast or splint is maintained for 6-8 weeks, or until x-rays show that the fracture has healed.
Left: Broken scaphoid bone with gapping across the fracture site. Right: Screw is placed inside the bone and across the fracture site, this squeezes the two pieces together to facilitate healing.
“Dr. Schreiber did an incredible job with my scaphoid surgery. The recovery time was much less than expected and after 3 months, my range of motion is almost back to normal. Would highly recommend Dr. Schreiber to anyone!”
Scaphoid Non-Union
Occasionally a scaphoid fracture is not diagnosed at the time of injury. If the fracture is not treated and the wrist is used normally, the motion across the fracture site can prevent the fracture from healing.
A fracture that has not healed is called a non-union.
Scaphoid non-union 1 year after injury. The fracture developed into a cyst, which filled in with scar tissue, but continued to produce pain.
In surgery for scaphoid non-unions, bone can be taken from the radius bone to fill in the defect.
If a non-union is caught early, before arthritis changes have taken place, it can be surgically treated.
In cases of delayed treatment, or “non-unions”, bone graft is often taken from the distal radius bone to help with healing. Sometimes this bone graft is taken with its own blood supply, called a “vascularized” bone graft. Healing of a scaphoid non-union typically takes several months, but is very often successful. Therapy is usually needed after the scaphoid has healed to restore wrist motion and flexibility.
Example 2. Scaphoid non-union 2 years after injury, with “cyst” formation inside the bone. Due to continued pain, and to prevent arthritis changes, the cyst was filled with bone graft from the distal radius and a compression screw was used to squeeze the two scaphoid fragments together. The fracture healed, and the pain resolved.
When a fracture is not treated, and the scaphoid is deprived of blood supply for a long period of time, the bone becomes avascular and necrotic (dead). This changes the shape of the bone, which over time results in arthritis throughout the surrounding bones of the wrist.
This pattern of arthritis is known as Scaphoid Non-union Advanced Collapse, or SNAC wrist. This can result in notable wrist pain and decreased motion. Other options are available for treating wrist arthritis.
Scaphoid non-union, resulting in necrosis of the scaphoid bone and arthritis throughout the wrist.
If you are a smoker with a scaphoid fracture, it is very important to quit to maximize the chance of healing. Nicotine constricts blood vessels, which decreases the blood supply to the fracture site and dramatically decreases the body’s ability to heal the fracture.
Dr. Schreiber is a board certified orthopedic surgeon specializing in hand, wrist, and elbow conditions. Dr. Schreiber practices at the Raleigh Orthopaedic Clinic in Raleigh, North Carolina.